Power transmission



June 4, 1946. v J VF JEANNIN 2,401,567

POWER TRANSMISSION Original Filed July 10, 1942 3 Sheets-Sheet 2INVENTOR. JOHN F. JEANNIN ATTORNEY.

Patented 101164, 1946 UNiTED vs'mrlzs PATENT OFFICE, Q I r rowsnzfiznssron Q John F. Jeannin. Detroit, Mich., assignor to van onIncorporated, Detroit, Mich a corporation of Michigan Originalapplication July 10, 1942, sci-m No.- 450,36 8. Divided and thisapplication May 20, 1944,SeriaiNo.536,489

1 This invention relates to power transmissions. particularly to thoseof the type comprising two or more fluid pressure energy translatingdevices,

one of which may function other as'a fluid motor.

The present application is a divisionof applicant's co-pendingapplication Serial No. 450,368, filed July 10, 1942, patented June 5,1945, No. 2,377,556.

The invention'is more particularly concerned with a compound pump unit.There is disclosed in the patent to Harry F. Viokers, No. 2,218,565,

as a pump and ana compound, positive-displacement pump circuit whereintwo or more pumps may be operated in parallel with the delivery pressurewhich they are pumping against low or moderate and, when such pressurerises to a higher value, they may be automatically reconnected to pumpin series.

The present invention is concerned with a compound pumping system ofthis character, and it is more particularly an object to provide asingle.

compact unitary device incorporating two pumps and all of the necessarycontrol valves and passages whereby they may be operated'either inparallel or in series depending upon delivery Pressure.

It is a further object to provide a structure of this character havingcertain constructional ad- I ure 1 showing a preferred form of thepresent invention. v

Figure 3 iii-across section on line 3-8 of Figure' 1.

Figure 4 s ure 1.

Figure 5 is a cross section on line 0-5 of Figure 1. a

Figure 61s .a cross section" on line 04 oi Figure V Figure 'l is acroiss section online 'l-I' of Fig a cross section on line 1-4 of Figure 1.

Figure 8 is a cross section on line 88 of Figure '4. j

Figure 9 is a fragmentary cross section taken 2 w l l on line 98 ofFigure 4 showing the relative arrangement of the pressure ports of thepumping units and pressure sealing means for the head plates thereof.

Referringnow to Figures 1 and 2 of the drawings, there is illustrated aunitary structure generally designated I 0 having two cylindricalrecesses i2 and I4 in axial alignment and within which are mountedrotary pumping cartridges or units l8 and i8. The latter may be of anysuitable type and as shown'are similar to the vane pump described in thepatent to Harry F. Vickers,'

No.- 1,989,900. Itwlli be understood that, although many of the detailsof the construction of such patented pump are omitted from the followingdescription, they may of course be considered as present in such unitsby reference.

Rotary units It and it, as shown in Figures 4 and '7, are identical inconstruction and comprise annular liner rings 20 and 22 which aresecured to the main body structure ill by screws 24 and 28,respectively. The inner surfaces of ring members 20 and 22 aresubstantially elliptical in shape togenerally form the balancedworkingchambers 28 and 30, respectively. The greater part of thesurfaces of the rings 20 and 22, which define the working chambers 28and 30, are substantially concentric a are also the diametricallypositioned portions 32 and 34 thereof which receive and support the mainbody of the rotors. By design.

pump i8, a first-stage unit, has a slightly larger volumetric output orcapacity than pump it, a second-stage unit. This is accomplished byforming the elliptical contour of the ringmember 20 of pump I6 with aslightly larger minor diameter than that of ring member 22, theirrespective tively long and narrow inlet ports 48. and It and 5|,respectively. (see Figures.

major diameters being equal. 7

The rotors of units i6 and it, as shown in Figure 2, are alsosupportedby opp sitely-positioned,

outlet ports 52 and 4 and '7);

' Pump units it and it are retained in their respective recesses" byhead plates 58 and I8 (Figure 2) J Thelatter are independently mountedand adapted to snugly fit within therecesses passage 88 (see Figure 8).

, of oil from within without.

vpressureover their respective units. Head plates 88 and 88 areadiustably secured by means of bolts 88 and82, respectively, to the mainbody structure I8. Also mounted thereto, by means of bolts 88 and 65,are bearing. platesv 84 and 88 which carry ball bearings 88 and 18,respectively, in which the ends of a shaft 12 are rotatably mounted. Itwill be noted that thejbearing plates 84 and 88 are.mountedindependently of the head plates 56 and 58 and of the shaft 12, and canbe securely aillxed without disturbance of Likewise, the

way affect the alignment of the shaft bearings. Shaft 12'is splined at14 and 18 to slidably re- Head lates 58 and 88 are provided withsealcommunicate with thepressure side of their rethe shaft 12, disposedradially thereof to connect with the pressure ports 82 and 84 of thepump units It and I8, respectively (Figure 9). As

ceive a broached complementary splined portion formed in the rotors ofunits I8 and I8 to provide a driving connection therefor.

shown in Figure 8, the pressure cores I48 and I28 extend upwardly beyondthe pump units and are separated by a common wall I22 through whichextend passages I24, of which only one is shown in Figure 8. Inalignment with the passage I24 is a bore I28 extending to the exteriorofthe body unit and normally closedby a threaded pipe plug I28. Slidablymounted in the bore I28 is a check valve I38 which is biased by a springI8I against an annular seat I32 carried by the borev I24. The latter isthus open to free flow from the passage I28 but is closed automaticallyto flow in the opposite direction, as during series operation late to bedescribed. a

Pressure core II8 (Figure 5) connects with a pasage I34 which extends tothe upper side of the is intersected by a transverse bore I88, whilepresspective pumps through passages 82 and 84, as

best shown in Figure-9. The head plates 58 and 88 also include drilledpassages 88 and 88 through which leakage fluid is drained to internalchambers 81 and 88 thereof. The latter chamber'communicates with thesuction side of the pump I8 through an obliquely extending passage 88.This provides for internal drainage of the unit I8 by having the fluiddrained into chamber 81 of the head plate 58 pass through the splines cfthe shaft 12 and into chamberg88 of the head plate 58, where it iswithdrawn by pump l8 through a End caps 82 and 84 are mountedonthe'bearing plates 84 and 88 by screws 98 and 88, respectively (Figure2). End

cap 94, because of internal drainage, carries a sealing ring I 88arranged to prevent the escape and the admission of air fromrespectively. The branch portions of the inlet cores I82 and I88, asshown in Figure 8, envelope their respective rotors, providing for theintake ,of liquid from both sides thereof to eliminate cavitation infllling the work chambers of the pump rotors.

The cores I82 and I84 both extend generally downward beyond the pumpunits and are there separated by a common single wall I88, as seen inFigure 8. A pair of check valves I88 are mountedin bores1l88 which areinalignment with bores III. These valves may be constructed as illustratedand described at 88 in the Herman Patent No. 2,288,392. The latterconnect the. two

cores I 82 and I84 and carry an annular seat H8 against which the checkvalve is normally urged into contact by a spring I'I2, the latterabutting against aplug II4. Core I84 (Figure '1) is provided with abranch portion II8 which extends therefrom to the bottom portionof theunit I8 to form a suction inlet for the two pump units I8 bores III(Figure 8) which are open to free flow from passage I84 but are closedautomatically by check valves I88 to flow in the opposite direction. asduring series operation hereinafter disclosed.

' and I8. The former unit draws fluid through the The body I8 is alsoprovided with cored pressure passages H8 and I28 (Figures 5 and 6) whichhave arcuate branch portions extending a ound unit I8 forming a deliveryconduit therefor, and

sure core I28 (Figure 6) connects with a passage I88 which leads to atransverse bore I48.

It will be noted from Figure 4 that the unit. I8

is provided with two suction check valves I88 and two pressure checkvalves I88 for the purpose of. rendering it compact and symmetricalabout its axis. The use of two check valves also enables their action tobe more rapid and reliable.

Mounted in transverse bores I88 and I48 (Fi ures 5 and 6) are relief andsequence valves I42 and I44, respectively.

is provided with an orifice I84 therethrough and a tubular pilot I88slidable in bore I88 in an end cap I 88. The latter is secured to theouter .face of the'body I8 to close the bore I88 and to provide acontrol chamber I82 for the relief valve piston I 48. A passage I 84,extends between the chamber I82 and a spring-loaded ball relief valveI88 mounted in chamber I 88.

Chamber I88 01 end cap I88 (Figures 3 and 4) communicates throughdrilled passageways I18 with the inlet core I82 01 the pump unit I8,which passageways serve as a drain therefor and also for another purposehereinafter disclosed. Briefly, the valve I48 acts to maintain apredetermined pressure in passage I84 (Figure 5) by opening anddischarging excess fluid into passage I12. Whenever a predeterminedpressure is reached, it causes the spring-loaded ball relief valve I88.to open and relieve control chamber I82 of liquid at a rate faster thancan be supplied through the orifice I84. This causes the piston I46 tobecome unbalanced and move to the right away from its seat I88 untilsufiicient pressure is restored to the control chamber I82. Since pilotover and above that existing in core 'I82.

Sequence valve I44 (Figures 3 and 8) comprises a valve spool I14slidably mounted in the bore I 48 and normally biased upward (Figure 3)by a spring I18 to cut'ofl port I18 from port I88. Port I18 connectswith the passage I88 (Figure 6) while port I88 connects with a passage I82 (see Figure 7) which extends to a core "4.1 The latter extendslongitudinally across the side of the body I8 and communicates with theinlet core I82 of pump I6 (see Figure 4) The upper end of the bore I48(Figure 3) of se- As shown in Figures 3 and 5, relief valve I42comprises a piston I48 slidcuence valve I88 is closed by an end capmember I88 containing a bore in in which is mounted an adjusting screwI98 for varying the pressure with the top of valve spool I18 wheneverthe setting of the spring I82 has been reached...

End cap member I88 includes passages 288 (see Figure '7) which connectthe bore I88 and the bottom 'of valve spool "8 with the inlet core I88to provide a drain therefor.

The unit I8 also incorporates a pressure dividvalve, the pressure in thedelivery conduit I88 will build up and, being transmitted to the smallpiston I88 (Figure 3) of the sequence valve I88, will overcome the forceof the spring I182 thereof,

thus opening valve l88 to connect ports. "8 and I88 thereof. This willbypass the delivery of pump I8 through passages I18, I88, I82 and I88(Figures 6 and 7) to the inlet core I82 '01 the pump unit I8 (Figure4),. This flow and that hereafter described are shown by dotted lines.

Pump I8'was previously pulling oil through the check valves I86, and thepressure dividing valve 288 was held closed by pressure in core I I8.Howing valve 288 (Figure 2) which causes the pumps I8 and I8 each tocarry its proportionate share of the main pressure during series flow,hereinafter described. Valve 288 comprises a diilerential piston 288mounted in a sleeve 2I8 which is fixed in a bore 2I 2. Piston 288 has anarea differential of one to two, of which the larger-area endcommunicates with the inlet core I82 of pump I8 through passage I18, andthesmallerarea end communicates through passage 2 I8 with the pressurecore. I I8 of pump I8. It will be remembered that core II8 connects withthe passage I38 (Figure 5) which forms the delivery conduit for thepumping unit I8,-thus constantly exposing the small end of pressuredividing valve check valves I88, This oil is drawn in through referenceis made for more detailed considerasuction ports 88 of unit I8 (Figure4) anddelivered through delivery ports 82 and into the pressure core II8(Figure 5). Pump I8 (Figure 7) draws in oil through suction ports 88 anddelivers the same through delivery ports 88 thereof and into thepressure core I28 (Figure 6) where it flows through pressure checkvalves I 88 (Figure 8) into the core II8.

With the parts of the control valves in the positionsshown, the combinedflow of the pump units It and 'I8passes through the deliver conduit I88to the work circuit so long as thepressure therein remains below thesetting of the sequence valve I88. Such how is indicated throughout thefigures by solid arrows. It will be understood that the relief valve I82is normally set for the maximum pressure of either pump unit, e. g.,1,888 p. s. 1., while the sequence valve I88 is given a pressure settingslightly below that of relief valve I82, e. g., 950 p. s. i. noted thatthe sequence valve I88 is operated by the pressure in the deliveryconduit I88 (Figure 3) through passage 282. Thus, so long as thepressure therein is below the setting of the valve I88, the latter willremain closed, and the entire discharge of the pumps itland I8, theircombined flow, is delivered through passage I88.

Under these conditions, if the pump unit I8 is adapted to drive a fluidmotor, such as a machine tool cylinder, the piston therein will move ata rapid traverse rate. As resistance to this movement is encounteredeither by meeting the work or by operation oi. a suitable iiow rate reduing It will be I ever, after the opening of-the sequence valve I88, pumpIt will receive its supply from the passages I82 and I88, and, as thisfluid is under pressure, it will cause check valves I88 to close. PumpI8 having a slightly larger capacity than pump I8, the surplus oil isreturned through the pressure dividing valve 286 to the inlet core I88of the pump unit I8. As hereinbefore disclosed, the pressure dividingvalve 288 is so constructed that the working pressure area exposed tothe pressure core II8 has a definite relationship to the work ingpressure area exposed to the inlet core I82 of the pump I8. Thisrelationship being one to, 8

passed from passage 2I8 to passage 2I8 (Figure The action of the presentpump circuit and its control valve is more fully described ,in thepatentto Harry F. Vickers, 2,218,565 to which tion of operation.

It will be seen that the present device provides an extremely compactunitary structure containing all the mechanism necessary to provide fordelivery of oil at a given volume and pressure by operating the twopumps in parallel or for delivery at half that volume and double thatpressure by operating the two pumps in series.

The construction furthermore provides several practical advantages,among them being that the head plates and bearing plates, pumpchamdlfiiculty in that the externally exposed bolts on I the pump areall of them such that they may be tightened to any degree withoutinterfering with the pump action, whereas, if the head plate bolts areexposed, they are frequently pulled up too tight by well-meaning butignorant workmen.

In addition, the main body casting provides,

by means of a few simple cores and a few drilled or bored passages, acomplete set of inlet and outlet passages for two balanced vane pumps aswell as making a housing for all of the control valves and providingall-of the circuit connections necessary for automatic series-parallelcontrol of such pumps. moreover are individually each of them of simpleand direct term and arranged to'carry the now This relationship is Thesecorings and passages to and from the points where it must be carried bypassages of minimum total length.

While the form of embodiment of the invention as herein disclosedconstitutes a preferred form, it is to-beunderstood that other formsmight be adopted, all coming within the scope of the claims whichfollow. What is claimed is as follows:

around both ends and periphery of the unit ad- Jacent and communicatingwith said inlet ports.

2. A rotary vane pump of the radially balanced type comprising a bodyhaving a cylindri- 1. A rotary vane pump of'the radially balanced typecomprising a body having a cylindrical pump receiving recess, a rotarypumping unit of cylindrical form positioned in said recess, said unithaving pairs of arcuate inlet ports positioned in the end faces of theunit adjacent the periphery thereof, and an inlet passage in the bodyextending from the outside of the body to the recess, said passageproviding a clear passage at a point adjacent and communicating withsaid inlet ports where the inlet passage intersects the pump receivingrecess.

JOHN F. JEANNIN.

